Other Voices: Grass Valley should heed San Juan Ridge mining lessons | TheUnion.com

Other Voices: Grass Valley should heed San Juan Ridge mining lessons

A recent op-ed piece in The Union concerning the safety of the Idaho-Maryland mine reminded me of the mining troubles that took place on the San Juan Ridge in the 1990s. It is a warning to everyone.

Siskon Mining acquired the rights to a mining project in 1992. Hydraulics has been used for mining in the area in the 1800s, leaving a large, open gravel space. It was believed that there was still a large amount of gold to be found on the Ridge. Several companies proposed open pit mines; Siskon’s plan was to dig through the surface gravel to the richer gravel of the tertiary level. The underground project looked much better to the San Juan Taxpayers Association than an open mine pit because there would be less noise, dust, lights, traffic, etc.

The Taxpayers Association decided to work directly with Siskon to make sure there were adequate safeguards in place, especially concerning ground water. The residents of the Ridge are dependent on their own separate wells. The association formed a committee and hired experts, when needed, to go very carefully through the Environmental Impact Report. Siskon’s EIR authors said that the mine and the homeowners sat on completely separate aquifers, and at worst, the level in a well would drop less than 1 foot. The Taxpayers Association’s geologist said that there easily could be fissures in the bedrock that would allow one aquifer to drain into the other.

The association negotiated a bond to cover expenses if anything went wrong. The initial bond was $40,500, which was to be increased by $13,500 annually. Also, Siskon was to replace any wells that went dry and pay into the bond the same amount as spent on well replacement. A committee to monitor water, noise, etc., was formed. The committee consisted of a community member, Siskon’s geologist and a member of the county planning department. Because the three principals could work directly with each other, they cut through a lot of bureaucratic red-tape and solved many problems quickly.

The first well went dry within two months of the beginning of digging. People could hear the rush of air down the well into the mine as water was pumped out of the shaft. Then the mine ran into a fissure, which increased the water that needed to be pumped from the mine from an estimated 215,000 gallons per day to 9 million gallons per day. The extra water was dumped into a local creek, flushing the creek sterile in violation of the water discharge permits. After two years of digging, the bond grew from $40,500 to $215,000. At least 17 wells went dry, including two at the local elementary school.

Eventually Siskon ran into unsolvable geological (and financial) problems and had to shut down.

The lesson for Grass Valley is to be very vigilant and tough in negotiating with the Idaho-Maryland people. Make sure there are safeguards to protect home owners, water companies and Wolf Creek from the potential damage done by the discharge of water from the mine.


Paul Moore lives in North San Juan.

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